How It Works-Book Of Dinosaurs

If you were to visit Queensland’s more

remote regions, you may very well fi nd

yourself standing face to face with one

of many 100-million-year-old beasts.

That’s because Queensland’s outback

was once part of the Great Inland Sea,

a huge swampy inland ocean that

existed in the age of the dinosaurs. As

such, hundreds of fossils have been

excavated from this region and there is

even an established ‘Australian

Dinosaur Trail’ that tourists can follow.

Queensland

Hind legs

Powerful rear legs allowed

it to hit around 29km/h

(18mph). It was probably

poor at turning though

Tail

A muscular tail helped

counterbalance the

T-rex’s heavy skull and

aided locomotion,

improving leg

retraction speeds

Oceans &

continents

1

Triassic

At the beginning of the

Mesozoic era in the Early

Triassic period, all the land

on Earth was joined together

into the supercontinent of

Pangaea, itself surrounded by

the superocean Panthalassa.

2

Jurassic

As the Mesozoic progressed

and the Triassic made way for

the Jurassic period, plate

tectonics split Pangaea into

two mega-continents:

Gondwana and Laurasia,

separated by the Tethys Sea.

3

Cretaceous

As the Mesozoic came to a

close, Gondwana and Laurasia

had split into many of the

continents we know today,

including North and South

America and Antarctica.

4

Palaeogene

In the Palaeogene period

• immediately following the
  K-Pg extinction – those
  continents continued to move
  to their current positions.

Beginning 252.2

million years ago

and coming to a

close about 65

million years ago,

encompassing a colossal stretch of

time that includes the Triassic,

Jurassic and Cretaceous periods, the

Mesozoic era truly defi ned the age of

dinosaurs. All the famous species you

can think of lived within it.

The Mesozoic was generally warm

with a signifi cantly smaller

temperature differential between the

equatorial and polar regions – ideal

conditions for the emergence and

proliferation of fl ora and fauna. Not

only was the Mesozoic famous for its

domination by dinosaurs, but also for

being the time period where the

ancestors of today’s major plant and

animal groups emerged.

Mesozoic world

Dinos organised their nests, laying their eggs

in patterns suggesting complex social

behaviours. Palaeontologists have identifi ed

two main types of egg-laying strategies –

clutches and linear patterns – further divided

by the shape of the nest and distribution of

eggs. For example, the ornithopod Maiasaura

nests generally consisted of bowl-shaped

excavations roughly two metres (6.6 feet)

wide and 0.8 metres (2.6 feet) deep, the

opening covered by loose vegetation. Each

nest was spaced roughly seven metres (22

feet) apart and was used by their offspring

until they were over a metre (3.3 feet) long.

Nesting &

dinosaur eggs

Outer shell

Dinosaur eggs were elongated and had

hard, brittle shells. Some of the largest

found to date were 0.6m (2ft) long

Embryo

At the centre lay the dinosaur embryo

that, depending on the species, could

take weeks or months to hatch

Amniotic membrane

Encompassing the dinosaur was a thin

membrane, helping keep the embryo

hydrated during development

Yolk sac

This contained proteins and fat which

served as food for the baby dino

Most of our current

knowledge of the

dinosaur kingdom comes

courtesy of

palaeontologists, who

dedicate their lives to uncovering the

secrets of their prehistoric kingdom.

From the earliest dinosaur hunters

such as Othniel Marsh (pictured left),

who discovered and named the

Allosaurus, Stegosaurus and

Triceratops, to 20th-century scientists

who revolutionised our understanding

of the dinosaurs’ legacy, such as John

Ostrom who gained fame for his

suggestion that birds were modern-

day descendants, palaeontologists

have helped provide tantalising

glimpses of the prehistoric world.

One of the more contemporary

palaeontologists who has helped

introduce dinosaurs to the general

public is Dr Philip J Currie. He is also a

museum curator who helped found the

prestigious Royal Tyrrell Museum of

Palaeontology in Alberta, Canada.

Palaeontology: key players

Pelvis

The T-rex was a saurischian

dinosaur, meaning it had a lizard

hip arrangement. Its pubis bone

pointed forward and down

rather than backward and down

like ornithischian species

“Weighing something like fi ve tons yet

walking bipedally makes the T-rex incredibly

interesting, as it pushes the absolute limits

of what is possible. I mean, you look at an

elephant and think, ‘Wow, that’s amazing’,

however, an elephant has to walk on four legs and

weighs roughly the same amount, so understanding

how T-rex functioned is a fascinating area of research”

DID YOU KNOW? Mesozoic means “middle life” in Greek

Body

Unlike popular depictions, it did

not stand vertical on its large

hind legs but leaned forward

with its body approximately

parallel to the ground